Researches in Earth Sciences
Year:2024 | Volume:15 | Issue:3|Papers Count:9

Introduction Net present value (NPV) index is one of the most important economic parameters in evaluating the mining investment projects. Considering the inherent uncertainty in effective parameters on the NPV in most of the mining projects, its precise estimation is a difficult process and application of the suitable methods is required. In this paper, fuzzy system, neural network and multivariate regression models are used for NPV determination in the Zarshuran gold mine project. In spite of the metal value, the effects of costs and discount rate on the NPV are also considered as an index for evaluation the Zarshuran gold mine project of Takab using the above models. One of the advantages of this research compared to the previous similar studies is the utilization of two new intelligent algorithms i.e., fuzzy system and neural network for modeling the NPV index with higher accuracy. These algorithms are efficient tools to solve the problems having ambiguity and uncertainty such as the mining investment projects and reduce the investment risks. Considering the management challenges in deciding on the economic justification of various projects and the existence of time and resource limitations, the use of these models helps clarify the economic future of a mineral investment project and make the final decision.   Materials and Methods In this study, three new models including fuzzy system, neural network and statistical multivariate regression were used to determine the NPV and evaluate the effective parameters on this index in the Zarshuran gold mine investment project of Takab. The obtained results of the above models were compared with each other, with the real data, and with the similar previous studies. Gold price (main element), silver price (byproduct element) and discount rate were considered as input parameters for evaluating the NPV. Application of the fuzzy logic in NPV modeling, which is always accompanied by uncertainty, can lead to more realistic results. Also, the utilization of neural network can be effective due to its high capability in dealing with vague and noisy data that are somehow involved in the evaluation of mining projects. Results and Discussion Using the trial and error method, triangular and trapezoidal membership functions, Mamdani inference motor and center of gravity decentralization function were determined as the optimum parameters of the proposed fuzzy model. Also, a neural network with training function of Levenberg-Marquardt back-propagation type, transfer function of sigmoid logarithm kind, 3-5-10-1 structure and root mean square error of 0.0032 was found as an optimum network. Moreover, a statistical multivariate linear relation was proposed to predict the NPV. According to the performance evaluation indices including determination coefficient, absolute error and relative error, results of the proposed models were compared with each other, with the actual data, and with the previous similar investigations. The above comparison proved that the performance of both fuzzy and neural models in predicting the NPV is acceptable and they have a much better agreement with real data in comparison with the statistical model. However, the performance of fuzzy model is somewhat better than the proposed neural network models in this research and previous studies and its results are more consistent with the actual data. Finally, the sensitivity analysis of the fuzzy model results (due to its greater accuracy) are conducted using the cosine amplitude method (CAM). Accordingly, it was confirmed that the gold price has the highest effect and the discount rate has the least effect on the NPV index.   Conclusion The present study proved the successful application of two new intelligent-based models including fuzzy logic and neural network algorithms to predict the NPV in the Zarshuran gold mine investment project. Also, a linear multivariate regression relation proposed to forecast the NPV index with a relative acceptable performance. Evaluation the results of proposed models showed that the fuzzy model performance was somewhat better than the proposed neural network models in this study and previous studies and both were much higher than the statistical model in predicting mining projects NPV. Based on the sensitivity analysis of the fuzzy model results (the most accurate proposed model), it was proved that the gold price and discount rate have the highest and lowest effects on the NPV, respectively. Considering the above results, it can be concluded that the proposed intelligent techniques in this research (especially the fuzzy model) can be used with good reliability in the evaluation of mining investment projects in order to cover their involved uncertainty and reduce the investment risk.

Introduction Enclaves provide valuable information for geologists, which includes the location of magmas, the nature of the host rock and the relative age of the masses, the dynamics of the magma chamber and cooling plutons, and various reactions inside the magma. The studied mass body (Sinavand Mountain) is located in the northeast of the Sonqor and in the Sanandaj-Sirjan zone with a relative age of Upper Eocene to Lower Oligocene. The purpose of this research is to investigate the field relationships and microscopic studies as well as the chemistry of amphibole crystals of the host rock and mafic microgranular enclaves (MMEs), for calculating of temperature and pressure of both the enclave and the host. The studied area consists of granodiorite-granite and diorite. The diorite rocks are exposed in the form of small and large enclaves with sharp edges and variable sizes. These enclaves are mostly angular, oval and shapeless with the contact margin often curved.   Materials and Methods This research is based on studies of geological maps, field relationships, thin sections and geochemical data. Plagioclase and amphibole minerals have been analyzed in Iran Mineral Processing Research Center (Karaj) using EMP analysis, in the time 15-20 seconds and a current of 20 Na.   Results and Discussion Petrography Host rocks: Granodiorite rocks are characterized by high abundance, medium grain and granular texture, and granites are medium to coarse grained and have granular texture. The host rock is composed of plagioclase (30-42%) with zoning and orthoclase (18-25%) and quartz (23-30%) and some secondary minerals of amphibole, titanite, biotite, apatite, zircon and metal oxides. Myrmikite, granophyric, poikilitic and perthitic textures are also observed. Enclaves: The composition of diorite enclave (up to quartz diorite) includes plagioclase (50-60%), amphibole (15-20%), potassium feldspar (less than 5%), quartz (3-15%) and secondary minerals apatite, sphene and Metal minerals. The texture is microgranular and sometimes there is chemical zoning that indicates chemical imbalance in the environment of their formation. Chemistry of crystals Amphibole: It is present in almost all compositions of host and enclave rocks, and 4 samples from each (8 samples in total) were selected and analyzed. According to the diagram of Si against Ca+Na+K, amphiboles in host rocks have igneous nature. Based on the charts of Lake et al., the amphiboles of the host rock are magnesio-hornblende and hastingsite, and in the enclaves, they are magnesio-hornblende and edenite. Plagioclase: The composition of plagioclase in granite is albite with a variation of anorthite content of 4 to 5% and albite granodiorite to oligoclase, but in diorite enclaves from oligoclase to labradorite and anorthite content is 20 to 55%. In both enclave and host, the composition of plagioclase is zoned and it will reflect the change caused by magmatic mixing/mixing. The dissolution reaction of more calcic plagioclase with a more sodic lava forms plagioclase that has less anorthite than the main types (i.e. core composition), but may be more calcic than its coexisting magmatic liquid. The significant textural and compositional imbalance between the calcic core and its sodic cover strongly indicates magmatic mixing and, of course, the durability and preservation of the signs requires rapid crystallization and incomplete mixing. The average pressure calculated for granite and granodiorite host rocks is 4.23 and 1.31 kbars, respectively, and the average pressure at the time of host mass replacement is 2.77 kbars. But the enclaves have a pressure of 2.46 kbars. Temperature has an effect on pressure calculation, and at high temperatures, the increase of tetrahedral aluminum in hornblende increases, and as a result, it increases the total aluminum and increases the pressure of mineral crystallization and magma replacement, which is true for enclaves.   Conclusion The macroscopic and microscopic characteristics of these enclaves, including grain size, morphology, presence of contact surface and different shapes of enclaves, the presence of elongated, shaped plagioclase crystals, needle apatite crystals and finally microgranular and poikilitic textures, indicate that these enclaves are the result of rapid cooling and mingling/ mixing of felsic and mafic magmas.

Introduction The Eocene deposits in the stuady area composed of a thick succession of pyroclastic, volcanic, and sedimentary rocks (Hajian, 1970). This study is mainly focused on the E5 lithozone in Takht-e Chakab area which is composed of tuff, sedimentary rocks and rhyolite. Based on Hajian (1970), the Eocene deposits are subdivided into 6 informal lithozones (E1 to E6).  i.e., the E1 unit are attributed to Ypresian–Lutetian and the E6 unit is attributed to Priabonian.   Materials and Methods In order to determine effective diageneic proceses in the studied succession, one stratigraphic section is selected which is located in Takht-e Chakab anticline, 35 km noth of Delijan city. 78 thin sections were prepared and analysed.   Results and Discussion The component allochems identified in the carbonate E5-5 lithozone including skeletal grains especially benthic foraminifera (Nummulitidae and Discocyclinidae), planktonic foraminifera, bivalve, gastropod, serpulids, bryozoa, red algae and corals. Hybrid samples consist of in-situ carbonte particles, clastic components, ash and volcanic particles. Petrographic studies of the studied deposits indicate that these sediments severly affected by diagenetic processes, which led to constructive and destructive porosity. One of the diagentic processes that affected Eocene carbonte deposits in burial environments is compaction. The mechanical compaction led to grain packing, deformation and sometimes crushed of the bioclasts. The grains contacts suturing and stylolite features are evidence of chemical compaction. Silicification is the main diagenetic processes in the studied section. Based on petrographic study some types of diagenetic silicification including chalcedony, micro and megaquartz that occurred in the form of secondary and replacement. Both selective and non-selective silicification is also recorded in some samples. Selectively silica replacement in the shell fragments, and pores filling siliceous cements were mainly filled interparticle porosities. The silica replacement of chalcedony type in bioclasts ocured as spherulitic replacement and controlled ones. The chalcedony fibers have radial pattern in the spherulitic replacement type and independent from microstructures of the test and its orientation. In contrast to spherulitic replacement, in the controlled type of replacement the position and configuration of chalcedony fibrous follow the microscopic structures of the test and showing preferntial orientation. The microcrystaline quartz with equant crystals is less than 20 µm (Maliva and Siever, 1988). In some of bioclasts microquartz is replaced in the form of silica. This process occurred in some bioclasts such as Assilina and Nummulites. Megaquartz occured as intraparticle and interparticle cements. While the interparticle cement involved higher frequently. The petrography of the studied succession reveals that the selective silicification is mostly take place in Assilina, Nummulites and, also ostera fragments. The effects of this process are not the same in different Nummulites species, as it is very common in larger shells rather than smaller ones. Silicification is more common in hyaline foraminifera, while it is absents in porcelaneous ones. Typically, this process is also different in hyaline foraminifera test (very developed in Assilina and Nummulites, it is, rare in Discocyclina, Actinocyclina and Asetrocyclina). The silica source for silicification is usually provided via the biogenic and volcanic activities (Robertson, 1977). Some authors considerd the dissolution of biogenic Opal and or volcanic glasses in as the sources of silica in connate waters, while others considered clay minerals alteration (Nobel and Van Stempvoort, 1989). Based on rare occurences of fossils with siliceous tests such as radiolarian and sponge spicules in the studied sections, the organic silica for this widespread silicification is not rational, so the volcanic materials are a valid source for silicification in these deposits (Okhravi and Mobasheri, 1997).   Conclusion The carbonate deposits belong to lithozone 5 (E5) consist of limestone, tuffa limestone and marl. Hybrid limestones are also observed in some horizons. Silicification as the main diagenetic process determined as replacing silica and pore-filling siliceous cement that influenced the studied strata. Skeletal factors play vital roles in type and amounts of silicification. Based on petrographic analysis, perforate hyaline foraminifera have undergo more silicification process in compare with other present bioclasts.

IntroductionGranitic to alkaline feldspar granitic masses of Mishu mountains, which are similar to them in the Moro mountains in the northwest of the country, are among the granitoid masses that are related to the Hercynian (Donian-Permian) orogenic cycle, and the study of their lithology and petrogenesis in order to complete the geological information. The northwest of the country is of particular importance and they contribute to our knowledge of the crustal formation of Iran during the Hercynian orogeny (Moayyed and Moazzen, 2002). Eftekharnejad et al. (1991) considered the mass of intrusive Shebster to be equivalent to Mishu granites. This massif has cut and transformed the Kahr and Dolomites of Sultanate. Permian base sediments were placed on the eroded surface of this intrusive mass and based on this, the age of this mass has been attributed to Post-Cambrian and Pre-Permian (Asadian et al, 1994). Due to the lack of determination of the A-type granites and the existence of some ambiguities about the Shabestar granitoid mass such as lithology and geochemistry (including the temporal relationship of the Shabestar granite mass with the adjacent masses and the orogenic phase of Iran), the Shabestar intrusive mass requires a comprehensive and comprehensive study to be a part of the history The geology of this area and the granite masses of the adjacent areas should be properly analyzed. Therefore, in this article, with the help of the results obtained from the study of the field relationships governing the different parts of the Shabaster intrusive mass, petrography and geochemical analysis of the main and rare elements, it has been tried to investigate the genetic relationship between the different parts of the mass, the origin of the magma that formed it, and the tectonic position of this intrusive mass. And finally, determine the A-type granites and compare them with S and I granites. Materials and MethodsIn general, conducting this research includes two stages of field visits and laboratory investigations. In the first surveys and field visits, 150 stone samples were taken from the internal igneous (Granitoid) masses of Shabestar, and from these samples, 110 microscopic thin sections were prepared for petrographic studies. In the next step, 20 samples were sent to ACME laboratory in Canada for geochemical analysis by whole rock method. Oxide analysis of main elements was done by lithium borate fusion method and inductively coupled plasma emission spectrometer (ICP-ES). In this method, the amount of oxides of the main elements is measured based on weight percentage. Results and DiscussionAlkaline mafic minerals such as ezirin-augeite and ribkeite-arphodsonite are not found in the examined granites, but all petrographic and geochemical data show that Harris granite rocks are of A-type nature. The comparison of the granite mass of East Mishu with the granite mass of Harris shows that this mass has a range of alkaline rocks of granite-monzogranite-siyenogranite. The dominant texture in these samples is fine-grained from the same dimension to the non-dimensional, perthitic and granophyric. The main minerals of these stones include quartz, potassium feldspar, plagioclase and minor and accessory minerals including biotite, amphibole, pyroxene, apatite, sphene and zircon, which are similar to the granites studied in this article. The negative anomalies of Ba, Nb, Ti, Sr, and Eu and the enrichment in LILEs, especially Rb and Thn, indicate the crustal origin of these rocks. Also, Ce and Sm show their enrichment compared to the adjacent elements. Such selective enrichment has been referred to as shell dominance (Pearce et al, 1984), and such a pattern is called shell dominance. In addition, these high values of HFSEs confirm the dry origin of the constituent magma (Bonin, 2007; Zhao and Zhou, 2007). ConclusionAccording to the field evidence, petrography, geochemistry and tectonic structure differentiation diagrams, Shabester granitoid mass is alkali feldspar granite. These rocks are covered by the Permian Formation and the Soltanieh Formation has recrystallized with it. Therefore, their relative age is attributed to Post-Cambrian and Pre-Permian. According to the alumina saturation index, the granitoid mass of Shabestar has peraluminous to weakly metaaluminous characteristics. Negative anomalies of Ba, Nb, Ti, Sr and Eu and enrichment in LILEs, especially Rb and Thn, indicate the crustal origin of these rocks. Therefore, Shabestar granitoid mass is A-type of in-plane granites of A-type, which is related to group A2 due to the depletion of Nb. In other words, it is very likely that A-type alkaline granites were created in this region after impact events, and during their emplacement, tensile tectonics prevailed. The REE diagram of these granites shows that the granitoid mass of Shabestar was probably due to partial melting of the lower crust with tonalitic-granodioric composition. The REE diagram of these granites shows that the granitoid mass of Shabestar was obtained from a plagioclase-containing source, or plagioclase was separated from the forming magma during the evolutionary process, so that it is probably due to partial melting of the lower crust with tonalitic-granodioric composition.

Introduction Meteorites are of interest to researchers as materials that have stored the history of the creation of the universe. However, the petrology of meteorites has received less attention in our country. In this research, two pieces of meteorites discovered in the Shahdad desert, located in the southwest of Lot Valley, have been subjected to petrographic and geochemical studies. The report of the discovery of this meteorite in 2018 was recorded in the World Bulletin. At present, there is a considerable diversity of topics within meteorite research. In addition, extensive petrographic and geochemical studies are being conducted in the field of classification and petrology of these rocks. In general, extensive and specialized research in this field is carried out in most of the world's leading universities, including European and American scientific centers (e.g., the Meteorite NASA Center and the G-Time Laboratory of the University of Brussels). The studied meteorite is also the largest chondritic meteorite discovered in Iran. This makes the subject of this study particularly important from the research point of view. The primary objective of this research is the petrographic and geochemical classification of the meteorite. Two pieces of the meteorite, which constitute a portion of a larger meteorite with an estimated mass of approximately 90 kg, were discovered in an area spanning 5 square kilometers in the western region of the Lut Desert and in the vicinity of Shahdad City in Kerman Province.   Materials and Methods The hand sample of meteorites from the Lut Desert in Iran displays a surface that is completely dark in color, ranging from dark brown to black. It contains regmaglypts and tension fractures resulting from impact with the Earth's surface. A thin melted crust, measuring 0.1 millimeters in diameter, covers the sample's surface. This crust reveals a fresh stone surface with a light brown color and gray to light brown speckles. The chondrules, which are known to be speckles, have a diameter ranging from 0.2 to 0.5 millimeters, with a density of 60 to 75 percent of the hand sample's surface (Figure 3 a).  The thin 0.1 mm diameter melt shell covers almost the entire surface of the sample. The presence of pyroxene and olivine compounds in the studied meteorite indicates that this sample belongs to the group of ordinary chondrites (OC) and is classified in the group of L and LL chondrites. The internal texture of the chondrules suggests that this meteorite belongs to the POP and BO groups, which are associated with meteorites that experienced high temperatures and cooling rates of 1000 to 1500 degrees per hour. Three pieces of this rock were crushed and powdered by hand for the purposes of chemical analysis.   Results and Discussion The presence of pyroxene and olivine compounds in the studied meteorite indicates that this sample belongs to the group of ordinary chondrites (OC) and is classified in the group of L and LL chondrites. The internal texture of the chondrules indicates that it belongs to the POP and BO group, which is related to meteorites with high temperature and cooling rates of 1000 to 1500 degrees per hour. The diagram of Al/Mn vs. Zn/Mn ratio (Figure 6) illustrates the locations of different types of common chondrites and typical examples of chondrites (known chondrites from around the world) (Kallemeyn et al, 1991, 1994, 1996, 1978, 1989; Kallemeyn and Wasson, 1982). The blue circles in this figure represent the Shahdad meteorite. The composition of the silicates and the chondrule boundaries of the studied meteorite indicate a fourth type of petrology. Given the absence of visible oxidation of metal or sulfide in the sample and the presence of a lemon-colored spectrum, it can be inferred that the degree of weathering is W0. In the majority of the examined sections of olivine crystals, a series of planar and irregular fractures on the olivine surface and plate fractures in the pyroxene mineral can be observed, which is indicative of remelting.   Conclusion According to the comparison of column charts of trace elements related to Shahdad meteorites with typical Antonin chondrites (L4-5). The composition of the elements of these two groups of meteorites are similar with a slight difference, which is a confirmation of the common chondrite of the L5 type of Shahdad meteorites. The classification of Shahdad meteorites by geochemical diagrams based on the amount of silica and alkaline elements and the diagram of alkaline elements (Na2O, K2O) versus silica indicates that Shahdad meteorites are alkaline. According to all the available evidence, the body of the mother asteroid of L5 Shahdad chondritic meteorites is a normal chondrite S asteroid type.

IntroductionCharacteristics of Badlands are the lack of vegetation, steep slopes and dense drainage network which are known as important sources of erosion and sediment production in the world. Heavy rains, scattered vegetation, low soil permeability, erodible materials, and steep slopes and slopes provide the conditions for badland faces. Badland erosion is affected by several soil properties, including surface soil depth, soil organic carbon content, organic matter status, soil texture and structure, available water holding capacity, and water transfer characteristics that determine soil quality. Cited. The extent of the influence of different physical and chemical factors of soil in the formation and spread of pustular erosion varies from point to point. Materials and MethodsThis study aimed to identify the most important factors of physical and chemical properties of soil and environmental factors and soil depth in the spread of badland erosion in Zanuzchay watershed. In this research, factors such as percentage of sand, silt and clay, PH, EC, SAR, organic matter, gypsum and soil lime in different altitude classes and the east-west direction and in three depths of 0-5, 5-30 and -30 60 Badland erosion faces were investigated. To investigate the effect of soil properties in different directions, altitudes and depths on the formation and development of badland in the study area, a systematic-random plan in the form of a factorial plan with two land use factors and altitudes, through analysis of variance and mean comparison was done by Duncan method. The normality of the data was assessed by the Kolmogorov-Smirnov normality test. Gypsum and SAR variables that had an abnormal state were normalized using root and logarithm of numbers, respectively, and parametric statistical tests were performed on them. Analysis of variance and Duncan's method were used to determine the effect of soil factors on Badland face formation.Results and DiscussionThe results obtained from unpaired t-test and Leven to compare the mean differences of some physical and chemical properties of Badland soils in comparison with control soils showed that the variables pH, SAR, gypsum, clay percentage, silt percentage, and organic matter they are significant at the level of (0.01). According to the investigation of the relationship between the physical and chemical properties of the soil and the formation of the erosion of badlands, it has been determined that the formation of badlands has a direct relationship with the percentage of clay, pH, EC, organic matter and SAR and has an inverse relationship with the amount of lime and gypsum. The results show that with the increase in salinity, the conditions for the establishment of plants decrease, which plays a significant role in reducing the speed of raindrops and their penetration into the ground. The results showed that the chemical factors of the soil largely determine the erosion and formation of badlands. In such a way that with the increase of pH and EC, the tunnel erosion increases and with the increase of lime and gypsum, the amount of sediment formation decreases. The increase of fine clay particles increases the stickiness of marl soil and with the increase of resistance against water action, surface erosion prevails. The increase in soil salinity and sodium absorption ratio causes the creation of fine granular structures in the soil, which disintegrate as soon as moisture reaches them. High amounts of sodium reduce the water conductivity of the soil through the phenomena of swelling and dispersion of clay minerals. The stability and resistance of grain soil decreases with the increase of sodium absorption ratio and as a result, soil erosion is intensified. Organic matter has a vital role on the chemical, physical and biological properties of soil, the change in the amount of organic matter due to its effect on biological activities, cation exchange, acidity and the amount of nutrients is one of the most important indicators of chemical and biological quality. It shows that organic matter plays an important role in the formation of soil grains and improves soil structure. The results obtained from Duncan's test show the difference between the means in different classes and directions and at depths of (0-5), (5-30), and less than 30 cm in both areas of Badland, and The control is at a significant level of 0.05. The results also showed that the average percentage of clay and sand at different heights have a significant difference at the level of 0.05. ConclusionConsidering the relationship between physical and chemical properties of soil with the formation of Badland erosive faces, many studies show that the formation of Badland has a direct relationship with the percentage of clay, pH, EC, organic matter, and SAR and is inversely related with the amount of lime and gypsum.

Introduction Examining the details between water and soil relationships can be useful and effective in better understanding these relationships that univariate regression can play an important role in this important matter and cause be a useful analysis of these relationships and ultimately the design of appropriate structures in water projects. The purpose of this study is to determine the type of relationship between runoff production and soil chemical properties using rainfall simulator, one of the advantages of which is to investigate the partial relationships that occur between runoff and soil chemical properties in different land uses in a shorter time, with lower cost and higher accuracy. Knowing the general information about a watershed is useful, but what leads to a better understanding of hydrological relationships in a watershed is knowing the details of hydrological relationships that have been discussed in detail in this research and can be useful and effective in the proper design of different watershed management structures in the watershed by increasing the understanding of the relationships between runoff production and chemical properties of soil, and also from wasting time experts and also prevented the waste of capital. In this research, it has been tried to state that sometimes a large amount of information obtained by different researchers in general may be not useful and also cause confusion for researchers, and paying attention to the details in the relationship between water and soil, even if it is small, has much more useful and better results for both researchers and the implementation department.   Materials and Methods In this study, in order to determine the type of relationship between runoff production and soil chemical properties in different land uses of Gachsaran Formation deposits, a part of Kuhe Gach watershed of the Izeh city with an area of ​​1202 hectares was selected.  The area has geographical coordinates of 49°45′27′ to 49°47′9′′ E and 31°50′ 27′ to 31°53′32′′ north. In this study, the relationship between runoff and soil chemical properties in different land uses of Gachsaran Formation was determined using univariate regression. Then, sampling of runoff production in 6 points with 3 replicates and in different rainfall intensities of 0.75, 1 and 1.25 mm/minute in three uses of the range, residential area and agricultural lands with the help of the rain simulator was done. In addition, the same number of runoff sampling was performed on soil chemical properties such as organic matter, soil salinity, soil acidity and carbonate calcium. SPSS and EXCEL software were used for statistical analysis. The rain simulator is known as the most important device for simulating different components of the hydrological cycle, especially rain and runoff resulting from it, in the first stages of formation and occurrence of soil erosion process. However, in recent years, the necessity of measuring runoff in order to evaluate it using rainfall simulation and in short-term times has been considered in order to manage watersheds.   Results and Discussion Soil chemical properties have a significant effect on runoff changes in different land uses, which were investigated in this study more detailed without interaction of chemical and physical properties of soil. Also, the complex role of soil chemical properties in relation to land use and runoff generation was shown. Although the displacement of rainfall simulators and the amount of water consumed in watersheds is very difficult, this study showed that the Kamphorst rain simulator can provide reliable and valuable data due to its easier displacement and homogeneous environment that its plot creates. Of course, one of its limitations is the height of the installation of the rain simulator, which is better to be placed at a higher height that is somewhat close to the terminal velocity of the raindrops. Therefore, it is recommended that instead of transporting soil from watersheds to fixed rain simulator laboratories, it is recommended to use simulators such as Kamphorst that can be easily transferred to watersheds.   Conclusion The results showed that in total, in Gachsaran Formation and in range, agricultural and residential land uses and in all three intensities of 0.75, 1 and 1.25 mm/min, soil organic matter in six cases had a negative relationship and in three cases showed positive relationship with runoff production. Soil salinity showed a negative relationship in five cases and a positive relationship in four cases, soil acidity showed a negative relationship in six cases and a positive relationship in three cases, and soil carbonate calcium had a negative relationship in eight cases and in one case showed a positive relationship with runoff production.  

Introduction Landslide is one of the natural hazards that causes a lot of human and financial damage every year in mountainous, rainy and seismic areas. Mass movements play an effective role in destroying communication roads, pastures, mountainous areas and causing erosion and sedimentation in watersheds. Identifying landslide-prone areas through risk zoning with appropriate models is unique of the main methods in reducing potential damage and hazard managing. Landslide susceptibility map preparation is known as the cornerstone of landslide research and is used as a management tool in times of crisis. Considering that the identification of landslide sensitive areas based on traditional methods and expert opinions is not accurate enough, the use of modern machine learning methods such as the support vector machine method seems to be necessary and necessary. The purpose of this research is to spatially model landslide susceptibility using two methods: generalized linear model (GLM) and support vector machine (SVM) and compare the efficiency of these models in zoning landslide susceptibility in Karganeh Watershed, Lorestan Province.   Materials and Methods Karganeh Watershed is one of the large sub-watersheds of Khorramabad with an area of 294.2 square kilometers. The minimum height of the this watershed is 1300 and the maximum is 2700 meters, and 60% of the area of this watershed has a slope of more than 12% (relatively high slope and more).The research method in this study is applied in terms of purpose and in terms of descriptive-analytical nature, library methods, field visits and modeling are used. On behalf of this goal, the distribution map layer of landslides in the watershed including 95 cases of landslides was prepared and separated into two sets for model training (70%) and model validation (30%) randomly.  Also, 16 causes disturbing the happening of landslides in this watershed were selected permitting to the review of sources and the usage of principal component analysis (PCA), Tolerance and VIF tests. Digital layers of effective factors in geographic information system were equipped. Slope factors, slope direction, elevation classes, geology, drainage network (distance from the river), road (distance from the road), fault (distance from the fault), topographic indicators (river power index (SPI), topographic moisture index (TWI) and Slope length index (LS)), geomorphological indices (topographic position index (TPI), topographic roughness index (TRI) and power vector index or surface roughness measurement (VRM) of land use, distance from the village, and rain lines as the most effective factors Landslide occurrences in Karganeh Watershed were known. Then, the landslide hazard map was prepared based on the two mentioned methods in the ModEco software environment. Next, in order to evaluate the accuracy of the modeling and compare the efficiency of the models, the relative performance recognition index (ROC) was used.   Results and Discussion By correcting the landslide data provided by the General Directorate of Natural Resources with the help of Google Earth satellite images and field visits, 95 landslides were identified, which cover an area of 1483.24 hectares of this watershed. Established on the fallouts of the maximum likelihood diagram, geological, land use, slope, topographic roughness index (TRI), slope length and slope direction are the best significant factors inducing the event of landslides in Karganeh Watershed. The results showed that the support vector machine (SVM) method with ROC equal to 0.913 was chosen as the best model for the basin. The generalized linear model with ROC equal to 0.803 also showed high efficiency in terms of landslide susceptibility evaluation. Permitting to the results of the support vector machine, about 19.3% of the Karganeh Watershed is in the high and very high hazard class of landslide happening. Based on the landslide susceptibility map with the support vector machine model, the villages of Jamshidabad Haider, Milmilk, Garmabala Bala, Bene Soura, Mahmoudabad Bala, Skin Bala, Cheshme Papi, Dareh Qasim Ali and Sheikh Haider are at high and very high hazard of landslides. It were located About 117 kilometers of communication roads in this area were classified as high and very high hazard.   Conclusion Established on the fallouts of this study, the maximum entropy algorithm provides practical results in order to zone the hazard of landslides in the Karganeh Watershed; By matching the obtained results by the existing real conditions, there is a very high agreement between the fallouts of the landslide hazard zoning map using this model and the real indication in this watershed. Assuming the concentration of management operations in high-sensitivity classes, about 70% of the area of the region will be removed from the management process and will cause the allocation of financial resources and less time. The implementation of landslide management programs based on the results of this research on a local and regional scale can explain the difficulties of domain instability and lead to the development of watershed management actions and the sustainability of the development of the Karganeh Watershed.

Introduction Cut-off  lows are cold -core cyclones in the upper troposphere that are identified as local minimums of geopotential elevation fields in the range of 500 and 200 hPa )Nito et al, 2008; Pinheiro et al, 2017; Muñoz et al, 2020(. Cut-off lows occur in most seasons, often in late winter and early spring. One of the synoptic patterns affecting temperature and precipitation as well as heavy rainfall in Iran is cut-off lows. This study has been compiled according to the importance and relationship between cut-off lows and heavy rainfall in the statistical period of 33 years (1986-2018). In this study, the climatology of cut-off lows systems at the level of 500 hPa of the northern hemisphere effective on heavy rainfall in Iran has been discussed. The ECMWF reanalysis data were used to identify and track cut-off lows that lasted for more than 48 hours in the statistical period of 33 years (1986-2018). For this purpose, geopotential, wind, and temperature data also were used.   Materials and Methods In this study, from the average daily data: Geopotential height, wind orbit, and temperature level of 500 hPa of the re-analyzed ECMWF European site with a grid step of 0.125 * 0.125 in the statistical period of 33 years (1986-2018) Used in areas including 0 to 80 degrees north latitude and 0 to 80 degrees east longitude. The Tibaldi-Multney index was used to identify Cut-Off low. And the Cut-Off lows that were effective in Iran's heavy rainfall were studied.   Results and Discussion Annual, monthly and seasonal distribution of cut-off lows during the statistical period In the statistical period of 33 years (1986-2018), a total of 632 cut-off lows with a lifespan of 2 days and more were identified. The average was 18.87 days for each year. The trend line or regression during the statistical period shows that the amount of cut-off lows is increasing. The share of cut-off lows in heavy rainfall in the four regions of Iran In the northwestern region of Iran, the highest percentage of the effect of shear compressions on heavy rainfall is in Kashan, Takab, Mahabad, Maragheh, and Tabriz stations, respectively. The lowest percentage of the impact of this phenomenon on heavy rainfall was in Khorramabad, Karaj, Babolsar, and Parsabad stations, respectively. In the southeast region, the highest percentage in Chabahar, Bandar Abbas, and Sirjan stations and the lowest percentage were in Jask, Zabol, and Khash stations. In the southwestern region, the highest effect is in Bushehr and Kish stations and the least effect is in Omidieh and Masjed Soleiman stations. In the Northeast, the highest share was in Birjand, Ferdows, and Tabas stations and the lowest impact was in Gorgan, Mashhad, Quchan, and Bojnourd stations. The amount of heavy rainfall and the effect of cut-off lows in it in different regions and Iran The highest occurrence of heavy rainfall due to cut-off lows was in the northwest region with (36.62 occurrences) and the lowest in the southeast region with (8.5 occurrences). In research study stations (76 stations), the frequency of heavy rainfall during the study period was average (124.76 events) and the effect of shear cut-off lows on heavy rainfall in total (26.1 events) in the station has been.   Conclusion A total of 632 cut-off lows with a lifespan of 2 days or more were identified in the research area. The trend line of the statistical period has a slight positive and increasing slope; the most occurrences of cut-off lows is in October, March, and January. The lowest incidence of cut-off lows is in July, August, and June. Seasonally, the highest number of cut-off low events was in spring, winter, and autumn. The highest occurrence of heavy rainfall under the influence cut-off lows was in the northwest region and the lowest in the southeast region during the study period. Therefore, it can be concluded that the entry of cut-off lows from the northwest and the proximity of the northwest region to the formation location of cut-off lows may be a factor contributing to the highest frequency of heavy precipitation events influenced by cut-off lows. Furthermore, the distance of the southeast region from cut-off lows indicates a lesser impact of this phenomenon on heavy precipitation in this area.